Electric primer.



op?. LINDSAY. i ELECTRIC PRIMER. APPLICATION FILED SEPT. 8, 1913.

. 745 A Patented Jan. 20, 1914.

INVENTOI? UNITED sTATEs PATENT orrion CHARLES F. LINDSAY, OF FAIRFIELD,CONNECTICUT, ASSIGNOB. TO THE UNION METALLIC CARTRIDGE COMPANY, OFBRIDGE'ORT, CONNECTICUT, CORPO- IRAJIIO- F CONNECTICUT.

smc'nnc munis.

Specieation of Letters Patent. v

Patented Jan. 2.0, 1914.

Animation mea septeinber s, ma. semi no. nasca.

To all 'whom 'it may concern:

Be it known that I, CHARLES F. LINDSAY, a subject of the King of GreatBritain, residing at Faireld, county of Fairfield, State of Connecticut,have invented an Improvement in Electric Primers, of which the followingis a specification.

This invention has for its obiect to prol vide an inexpensive andgreatly improved electric primer so constructed that all pressuresexerted in the primer tend to tighten -up the parts making it absolutelygas tight,

With these and other objectsin vievv I .have devised the novel electriprimer Which I Will now describe referring to the accom` panying drawingforming a part of this specification and using reference characters toindicate the several parts.

Figure l is a vievv of one form of my novel primer in longitudinalsection; Fig. 2 a vievvvof the connecting Wire detached; and Fig. 3 isa- View partly in elevation and partly in longitudinal section,illustrating a slightly variant form of the invention.r`

10 denotes the shell which is drawn from sheet metal and is providedwith a head 11 having a central opening 12.

13 denotes the contact butt-on which lies flush With theouter face ofthe head of the shell and the inner end of which is provided Wit-h ahead 14 of greater diameter than the opening in the head of the shelland prefer-v ably, although not necessarily, provided With a recess 15,and 16 is a Washer in electrical contact With the shell and having anopening 17. Between the contact button and the contact Washer gun cottonor some other explosive, indicated by 18, is placed, the explosive beingshown as filling the recess in the contact button and extending throughthe opening in the contact Washer. The contact button' is separated andinsulated from the head and Wall of the shell and also from the contactWasher by means of insulating rings 19 .and 20, said rings being formedto a. suitable shape in 'cross section to correspond with the shape ofthe contact button and to permit them to drop to place readily inassembling. Contact ring 19 fills the space between the contact buttonand the wall of opening 12 in`A the head of the shell and'also separatesthe head of the c ontact button from the head ofthe shell, andinsulating ring 20 separates the head of the contact button from theWall of the shell and also separates the head of the contact button fromthe contact Washer. The electrical circuit is completed and theexplosive is ignited by means of a Wire 21 which passes diagonallythrough the explosive and lies in close contact with the Contact buttonand the contact washer.y

The forms illustrated inl Figs. 1 and 3 differ only in the shape oftheinsulating rings and in the interposition between the insulating ring orrings and the wall of the shell of a'metallic Sleeve, indicated by 22,nflhiltlzh extends forward from the head of the s e In assembling, whensleeve 22 is used, the

insulating rings, contact button, sleeve, explosive, connecting Wire andcontact washer may be assembled in the shell and then the end of thesleeve may be crimped down ont-he contact Washer as at 23, in Fig. 1 andthen the parts are locked in place by indenting the shell or by rollinga circumferential groove 34 therein,.or if preferred, sleeve 22 mayvfirst be crimped and the parts of the primer placed therein and theninserted in the shell, after which the shell is indented o1' the grooveis rolled therein as before.

In the form illust-rated in Fig. 3, the parts comprising the primer areassembled in the shell as irst described, with the exception that thesleeve is omitted, after which the groove is rolled in the shell to lockthe electrical parts of the primer in place. In either form, it shouldbe noted that the electrical parts of the primer are securely lockedin'place, at the back by the head of the shell and at the front byindentations or the rolled in groove. The groove holds the electricalparts against forward movement. when engaged by the electric firing pinof 'a gun and the head of the shell holds' said parts against backwardmovement under the pressure of the gas generated Within the primer andcauses the insulating rings, and the metallic sleeve if used, to makethe primer absolutely gas tight, which is a vitally important feature ofthe invention.

The primer is completed by nearly filling the shell with rifle powder orsome other eX- plosive, indicated by 25, placing over the rifie powder aWad 26 and then crimping the end of the shell as at 27. In firing, thecurrent passes from the ring mechanism of the gun to the contact button,thence through the wire to the contact washer and ignites the guncotton, the flame of which passes through the opening in the contactwasher and ignites the riie powder, which in turn ignites the explosiveof the'shell in which the primeris used, which is not illustrated as itforms no portion of the present invention. y

Having thus described my invention I claim:

1. In a structure of the character 4de-1 scribed, the combination with ashell' hav- `ing a head with a central opening, of a conwall of theopening, a contact washer, an explosive between said button and washer,a bridge wire passing through the explosive and connecting said buttonand washer, and an indentation in the shell whereby the parts are lockedbetween said indentation and the head of the shell.

2. Ina structure of the character described, the combination with ashell having a head with a central opening, of an insulated contactbutton seated in saidv opening and having a head of greater diameterthan t-he opening, a contact washer, a sleeve-abutting against the headof the shell and forth, an explosive between said button' and washer, abridge wire passing through the explosive and connecting said button andncrimped over the washer, for the purpose set Washer, -and anindentation in theshellv whereby the parts are locked between saidindentation and the head of the shell.

In testimony whereof I aix my signature in presence of two Witnesses.

CHARLES F. LINDSAY. Witnesses:

WM. H. SKINNER,

GEO. T. WURM.

